How Are the Environmental Grades of Water-based Paint Classified

Environmental grades of water-based paint are measured by several dimensions. VOC content: lower is better. China's HJ 2537-2014 requires quality water-based paint VOC under 100 g/L; GB 18582-2020 limits it to <=80 g/L, with interior wall <=100 g/L, exterior <=200 g/L, wood/anti-corrosion/waterproof <=250 g/L. Europe is stricter at generally VOC<15 g/L. Limited harmful substances: benzene, toluene, xylene, ethylbenzene and halogenated hydrocarbons <=500 mg/kg; formaldehyde and its polymers <=100 mg/kg; mercury <=60 mg/kg, lead <=90 mg/kg, cadmium <=75 mg/kg, chromium <=60 mg/kg; free TDI in water-based polyurethane curing agents <=5000 mg/kg. Together these thresholds define a paint's environmental grade.